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691.
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Nicholas A.O. Hill Keith P. Michael Allen Frazer Stefan Leslie 《Ocean & Coastal Management》2010,53(11):659-668
Local ecological knowledge (LEK) has been recognised as an important source of information for resource management in data-poor fisheries. Our case study of the Foveaux Strait dredge oyster fishery in New Zealand shows LEK can also make a significant contribution to the management of data-rich fisheries, but highlights the importance of appropriate data collection design and interpretation and presentation of LEK. We formalise a structure for interpreting LEK, illustrate the importance of design by comparing two LEK studies, and discuss how the inclusion of LEK into the fisheries plan process has provided unexpected benefits for better management of the fishery. 相似文献
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Elisabeth Bondar-Kunze Stefan Preiner Friedrich Schiemer Gabriele Weigelhofer Thomas Hein 《Aquatic Sciences - Research Across Boundaries》2009,71(4):437-447
This study evaluated the effects of a controlled surface water connectivity scheme on several backwaters in an urban floodplain
within the city limits of Vienna, the Upper Lobau. A phosphorus budget and ecosystem metabolism measurements were used to
assess the reaction of two trophically distinct floodplain backwater sections on changed connectivity conditions. The surface
water connection led to a reduction of the retention times in the backwater system. The water column nutrient concentrations
in the individual backwater sections approached those of the source water body. The significance of these effects, however,
depends on the historical and current trophic situation of the respective water bodies. Generally, the surface water connectivity
introduced particulate phosphorus export up to 30% increase over the influent loading and dissolved phosphorus up to 14% increase
over the influent loading. However, in sections with submersed macrophyte development, which provided enhanced filtering capacities
for particulate matter, sediment and phosphorus accumulation rates were increased. At the same time, water transparency increased
resulting in a positive feedback supporting further macrophyte development. Based on these findings, the evaluation of restoration
measures in urban floodplains needs to consider the spatial and temporal dynamics of nutrients and ecosystem processes such
as gross primary production and community respiration to predict long-term development. 相似文献
696.
Geomorphic evidence of former glaciation in the high Drakensberg of southern Africa has proven controversial, with conflicting glacial and non‐glacial interpretations suggested for many landforms. This paper presents new geomorphological, sedimentological and micromorphological data, and glacier mass‐balance modelling for a site in the Leqooa Valley, eastern Lesotho, preserving what are considered to be moraines of a former niche glacier that existed during the Last Glacial Maximum (LGM). The geomorphology and macro‐sedimentology of the deposits display characteristics of both active and passive transport by glacial processes. However, micromorphological analyses indicate a more complex history of glacial deposition and subsequent reworking by mass movement processes. The application of a glacier reconstruction technique to determine whether this site could have supported a glacier indicates a reconstructed glacier equilibrium line altitude (ELA) of 3136 m a.s.l. and palaeoglacier mass balance characteristics comparable with modern analogues, reflecting viable, if marginal glaciation. Radiocarbon dates obtained from organic sediment within the moraines indicate that these are of LGM age. The reconstructed palaeoclimatic conditions during the LGM suggest that snow accumulation in the Drakensberg was significantly higher than considered by other studies, and has substantial relevance for tuning regional climate models for southern Africa during the last glacial cycle. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Joshua E. Cinner M. Aaron MacNeil Xavier Basurto Stefan Gelcich 《Global Environmental Change》2013,23(6):1359-1365
The common scientific and media narrative in fisheries is one of failure: poor governance, collapsed stocks, and vanishing livelihoods. Yet, there are successful fisheries – instances where governments and/or communities have maintained or rebuilt stocks, where fishers have robust livelihoods, and where institutions are strong. Scientists and managers alike are becoming increasingly interested in moving beyond the doom-and-gloom stories of fisheries failures toward cumulative knowledge for making fisheries governance more successful. Recent literature has attempted to determine what separates the successes from the failures and better understand how lessons learned for effective fisheries governance can be cumulatively compiled. In this special issue, we present a range of fisheries studies from around the world – Latin America, The Pacific, and East Africa. The studies look at varying fisheries outcomes, including sustainability, cooperation, self-governance, and sustaining livelihoods. The contributions in this special issue all tackle the challenge of exploring, testing, and refining the Diagnostic Framework for Analyzing Social-Ecological Systems developed by Elinor Ostrom as a way to cumulate knowledge on the potential conditions that could be causing a problem or creating a benefit in the governance of small-scale marine fisheries. These articles successfully explore the applicability and contributions of the framework while providing important theoretical refinements for small-scale fisheries. 相似文献
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Martin Bruckner Stefan Giljum Christian Lutz Kirsten Svenja Wiebe 《Global Environmental Change》2012,22(3):568-576
Production and consumption activities in industrialized countries are increasingly dependent on material and energy resources from other world regions and imply significant economic and environmental consequences in other regions around the world. The substitution of domestic material extraction and processing through imports is also shifting environmental burden abroad and thus extends the responsibility for environmental impacts as well as social consequences from the national to the global level. Based on the results of the Global Resource Accounting Model, this paper presents the first trade balances and consumption indicators for embodied materials in a time series from 1995 to 2005. The model includes 53 countries and two world regions. It is based on the 2009 edition of the input–output tables and bilateral trade data published by the Organisation for Economic Co-operation and Development (OECD) and is extended by physical data on global material extraction. The results quantify the global shift of embodied material resources from developing and emerging countries to the industrialized world. In addition to the level of industrialization and wealth, population density is identified as an important factor for the formation of physical trade patterns. Exports of embodied materials of less densely populated countries tend to surpass their imports, and vice versa. We also provide a quantitative comparison between conventionally applied indicators on material consumption based on direct material flows and indicators including embodied material flows. We show that the difference between those two indicators can be as much as 200%, calling for an adjustment of conventional national material flow indicators. Multi-regional input–output models prove to be a useful methodological approach to derive globally consistent and comprehensive data on material embodiments of trade and consumption. 相似文献
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